I was at the SF React Native developers meet up the other night, the speaker (Devin Abbott) gave several nice pro/con's slide re react native. Here's a picture of the slides:
I don't think Facebook backing Parse is relevant. React Native was designed by Facebook, so I'm assuming they understood the design choices of the mobile ecosystem at the time.
Parse was an acquisition by Facebook that didn't end up working out.
Yeah, it really depends on what your needs are. React Native has a lot of cool features but it also has quite a steep learning curve if you are new to React or new to Native development.
http://imgur.com/a/T3O7i http://imgur.com/a/z2oIU